fix(android): use reactApplicationContext.currentActivity for RN 0.87

[jellebreuer]

Fixes #15.

On React Native 0.87 the Android build fails with:

e: .../com/speech/RNSpeechModule.kt:733:22 Function invocation 'getCurrentActivity()' expected.

Cause. ReactContextBaseJavaModule was converted to Kotlin in 0.87, so getCurrentActivity() is now declared as a protected fun rather than a Java getter. Kotlin's synthetic property access only applies to Java getters, so currentActivity no longer resolves and the compiler demands an explicit call.

Fix. The method has also been deprecated since 0.80.0, and its annotation names the replacement directly:

// ReactContextBaseJavaModule.kt
@Deprecated(
    "Deprecated in 0.80.0. Use getReactApplicationContext().getCurrentActivity() instead.",
    ReplaceWith("reactApplicationContext.currentActivity"),
)
protected fun getCurrentActivity(): Activity? = reactApplicationContext.currentActivity

Using that replacement fixes the build and removes the deprecation warning at the same time, which calling getCurrentActivity() explicitly would not.

Compatibility. This should be safe across React Native versions rather than trading one break for another. Both accessors it goes through are still Java getters — BaseJavaModule.getReactApplicationContext() is protected final and ReactContext.getCurrentActivity() is public @Nullable — so synthetic property access remains valid on older releases too. reactApplicationContext is also what the deprecated method itself delegates to, so behaviour is unchanged.

Verification. Built against React Native 0.87.1 with the New Architecture on Android (compileSdk 37, AGP 9, Gradle 9.4.1): :mhpdev_react-native-speech:compileDebugKotlin and a full :app:assembleDebug both succeed, with no deprecation warning. Text-to-speech works on device. Only openVoiceDataInstaller is touched.

[Mhp23]

LGTM! Thanks for the PR.